Framework-free building system and method of construction

ABSTRACT

An easily constructed and highly durable structure, and method of making the same. The structure is constructed of lightweight foam panels assembled into walls and a roof, and therefore requires no framework. The entire structure is then sprayed with a cementitious coating. The cementitious coating is applied directly to the foam panels, and dries with sufficient strength and durability to make the structure load-bearing.

RELATED PATENT APPLICATIONS

[0001] This patent application is a continuation of U.S. Ser. No.09/490,505, filed Jan. 25, 2000, which claims priority to United StatesProvisional Application No. 60/117,115, filed Jan. 25, 1999, andentitled FRAMEWORK-FREE BUILDING SYSTEM AND METHOD OF CONSTRUCTION; saidapplications in their entirety are hereby expressly incorporated byreference into the present application.

BACKGROUND OF THE INVENTION

[0002] This invention relates to a foam panel building system that isbonded together with a sprayed-on cementitious coating that forms aload-bearing shell around the entire structure.

[0003] There are numerous methods for constructing homes and buildingstructures, and each have their benefits and drawbacks. The most commonhome building method in the United States, for instance, involvesbuilding a wood frame structure, which is then faced with brick orsiding of a variety of materials, and finished with drywall and paint onthe interior. Building such a home takes considerable time, requiresworkers with a variety of skilled trades, and incorporates numerousdifferent materials. While this building method is highly flexible, itis often quite costly.

[0004] The most common building method throughout the rest of the worldinvolves building a structure with blocks made of a wide variety ofmaterials, including mud, brick, or concrete. While relatively simpleand inexpensive to construct, such building methods are time consuming,often require skilled laborers, and frequently require materials notreadily available in every location.

[0005] There are many places in the world that are without the necessarybuilding materials and skilled workers, and where the local populationcannot afford to construct homes. Thus, there is a need throughout theworld for buildings that are highly durable, yet quick, easy, andrelatively inexpensive to construct. This invention meets that need byproviding a structure that requires few components and is quick andsimple to construct, resulting in a relatively inexpensive method ofconstruction.

[0006] There are a number of patents covering lightweight foam panelbuildings covered with cementitious material, but none have the featuresof this design. One of the earliest is U.S. Pat. No. 3,676,973, issuedon Jul. 18, 1972 to Kellert, which contains an elaborate structuralframework, and also requires a wire screen for application of sprayed onconcrete. Another example is seen in U.S. Pat. No. 4,292,783, issued onOct. 6, 1981 to Mulvihill, which requires the use of a temporaryframework to assemble the panels, and then requires a rigid steel wiremesh for application of a gunnite concrete layer. A third example, U.S.Pat. No. 4,342,180, issued Aug. 3, 1982 to Gibson et al., requires asteel framework to hold the panels in place, and requires wire mesh forapplication of the concrete. The necessity of a framework, eithertemporary or permanent, increases the cost and complexity of thebuilding method. The present invention does not require a framework tohold the structure in place, making it easier, quicker and cheaper touse.

[0007] One unique aspect of this invention is that the cementitiousmaterial is sprayed directly on the structure without the need for wireor other meshing to hold the material, unlike stucco or otherconventional materials.

[0008] The current art contains a number of spray-on cementitiousmaterials, which have two drawbacks. Many cannot be applied directly toa surface, requiring the use of a wire or mesh covering over thesurface. Others can be applied directly to a surface, but provide nostructural support. The present invention does both.

[0009] Examples of prior art in these categories includes U.S. Pat. No.4,774,794 issued Oct. 4, 1988 to Grieb, which discloses pre-made foamblocks with a cementitious coating. The coating is applied on afiberglass reinforcement mat laid over the surface prior to theapplication of the coating. While these blocks are of sufficientstrength to create a load-bearing structure, they have the disadvantageof requiring a mesh to apply the cementitious coating. A similar exampleis U.S. Pat. No. 4,150,175 issued Apr. 17, 1979 to Heutteman, disclosesa building panel made from a honeycombed core panel covered with a thin,strong concrete coating. Both inventions require assembly after coating.

[0010] A second unique aspect of the present invention is that thecementitious material dries hard enough to make the materialload-bearing. There are many spray-on materials known in the art, suchas cement or stucco, but these do not add structural strength or supportto the building. There are a few patents on the direct application ofcementitious materials to a surface, but none produce a structure thathas load-bearing properties. For example, U.S. Pat. No. 4,067,164,issued Jan. 10, 1978 to McMillan, shows a panel with a directapplication of cementitious materials, which provides protection to theunderlying materials, but does not produce any structural benefits.

[0011] Another example from the prior art is U.S. Pat. No. 5,771,649issued Jun. 30, 1998 to Zwieg. It is drawn to a system of structuralfoam and plastic blocks, which are then coated with a sprayed onconcrete. In Zwieg, the blocks provide structural support and theconcrete provides a protective layer.

[0012] From the preceding description of the prior art, it should beapparent that there is a need for a building system that is simple tobuild, yet structurally sound. This invention meets that need.

SUMMARY OF THE INVENTION

[0013] The present invention is directed to a new foam panel buildingsystem that is bonded together with a cementitious coating that forms aload-bearing shell around the entire structure, and to the method ofconstructing this structure. The building system is comprised of anumber of foam panels, a means for connecting the panels into wall unitsand a roof, and a cementitious coating applied directly to the walls androof which forms a load-bearing shell.

[0014] It is an object of the present invention to provide a more easilyconstructed and more durable building system than that which haspreviously been available in the industry. Moreover, the presentinvention provides a building system that is not only strong, but isalso aesthetic in appearance. It can be easily adapted to incorporate agreat variety of architectural details to suit a purchaser's specificneeds. Importantly, the invention also provides a low-cost housingalternative that is quick to construct.

[0015] It is an additional object of this invention to provide acementitious coating that is applied directly to a surface without theneed for wire or mesh to hold the coating. It is a further object ofthis invention that this cementitious coating, once applied to asurface, provides sufficient strength and durability to create aload-bearing structural element.

[0016] The method of constructing this structure comprises the steps ofbuilding a foundation, attaching panels to create walls, attaching wallsto the foundations and then to each other, attaching panels to create aroof, and applying a cementitious coating onto the walls and roof toform a load-bearing shell around the structure.

[0017] Still other objects, features, and advantages of the presentinvention will be apparent from the following description of thepreferred embodiments, given for the purpose of disclosure, and taken inconjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018]FIG. 1 is a plan view of the preferred embodiment of the buildingsystem showing the location of the exterior and interior walls on thefoundation.

[0019]FIG. 1A is a cross-sectional view of a wall showing thecementitious material being sprayed in a thin coating to produce theload-bearing shell.

[0020]FIG. 2 is a plan view of the foundation showing the location ofthe trenches under the exterior and interior walls.

[0021]FIG. 3 is a cross-sectional view of the foundation at across-section showing the trench at the edge of the foundation beneaththe exterior wall.

[0022]FIG. 4 is a cross-sectional view of the foundation at across-section showing the trench under an interior wall.

[0023]FIG. 5 is the front elevation view of the preferred embodimentshowing multiple vertical foam panels positioned side-by-side and cut ata slant to match the pitch of the roof, and joined together to form thefront wall.

[0024]FIG. 6 is the back elevation view of the preferred embodimentshowing multiple vertical foam panels positioned side-by-side and cut ata slant to match the pitch of the roof, and joined together to form theback wall.

[0025]FIG. 7 is the right elevation view of the preferred embodimentshowing multiple vertical foam panels positioned side-by-side and joinedtogether to form the right wall.

[0026]FIG. 8 is the left elevation view of the preferred embodimentshowing multiple vertical foam panels positioned side-by-side and joinedtogether to form the left wall.

[0027]FIG. 9 is a detail view of an alternative embodiment showing theuse of a spline as a connection between two adjoining wall panels.

[0028]FIG. 10 is a detail view of an alternative embodiment showing theuse of a spline as the connection between two adjoining corner wallpanels.

[0029]FIG. 11 is a detail view of an alternative embodiment showing theuse of a spline as the connection between two adjoining exterior wallpanels and an adjoining interior wall panel.

[0030]FIG. 12 is a detail view of an alternative embodiment showing theuse of a spline as the connection between two adjoining corner wallpanels and an adjoining wing wall.

[0031]FIG. 13 is an interior elevation view of the preferred embodimentshowing multiple vertical foam panels positioned side-by-side and joinedtogether to form a wall.

[0032]FIG. 14 is a roof plan view of the preferred embodiment showingmultiple foam panels positioned side-by-side and joined together to formthe roof.

[0033]FIG. 15 is a roof plan layout view of the preferred embodimentshowing multiple foam panels before being joined.

[0034]FIG. 16 is a detail view of an alternative embodiment showing theeave, the bevel cut on a wall, a notch cut into the underside of theroof to receive the top edge of the wall, an outer roof notch cut intothe upper roof surface with an outer roof rib placed in the outer roofnotch, and a spline connecting foam panels of the roof.

[0035]FIG. 17 is a detail view of an alternative embodiment of the ridgeof the roof, showing a bevel cut on the top edge of the interior wall,notches cut into the underside of the roof to receive the top edge ofthe wall, the apex roof notch cut into the apex of the roof, the apexroof rib placed in the apex roof notch, and splines connecting foampanels of the roof.

[0036]FIG. 18 is a perspective view showing the assembled structure inthe alternative embodiment with the hurricane straps and a door andwindows.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0037] Referring to the drawings, FIG. 1 shows a preferred embodiment ofthe present invention where the building system is a house 2 built on aconcrete foundation 4 that is preferably a reinforced concrete slab.However, a wide variety of housing foundations may be used, as iswell-known to those skilled in the art. In the most preferredembodiment, a welded wire mesh 9, as shown in FIGS. 3 and 4, is used toreinforce the concrete and No. 6 mesh (the wires run perpendicular toeach other at about 6 inch intervals). The wire fabric 9 is laid in agrid work pattern and is bent on the ends into a trench 10 that isexcavated around the perimeter 8 of the concrete foundation 4, asfurther shown in FIGS. 2 and 3. The foundation 4, in another preferredembodiment, may be constructed with a system of I-beams placed under theperimeter 8 of the house 2 as well as under the interior walls 5.Concrete is poured around the I-beams.

[0038] The dimensions of the concrete foundation 4 should match thedimensions of the house 2 at ground level, plus any porches or patiosaffixed to the house 2. The dimensions of the foundation 4 may be anysize, but in the preferred embodiment of a small house, are about 24feet by about 20 feet. In addition, the foundation 4 is in the rangepreferably of about 2 inches to about 6 inches in thickness. In onepreferred embodiment of the invention, the concrete foundation 4 isabout 2 inches thick across the entire foundation 4, except wheretrenches 10 are formed around the perimeter 8 of the house 2 and underany walls 6 of the house 2. Preferably, the trenches 10 are about 4inches deep and about 6 inches wide and create additional support underthe walls 6 of the house 2. FIG. 3 shows a cross-section of the trench10 across the line A-A in FIG. 2. FIG. 4 shows a cross-section of thetrench 10 under an interior wall 6 of the house 2 across the line B-B inFIG. 2.

[0039] As shown in FIGS. 5 and 6, the interior walls 5 and exteriorwalls 6 of the house 2 are constructed of foam panels 20. The foampanels 20 may be made of expanded polystyrene (“EPS”), polyurethane orother foamed plastics. EPS panels cut to the proper size may be readilyobtained from foam companies and are preferably modified EPS with apound per cubic foot density in the range of about 1.0 to about 2.0(Houston Foam Plastic, Houston, Tex.). In the preferred embodiment, thefoam panels 20 are pre-cut and numbered consecutively so that they areeasily assembled at the construction site and easily matched up with thehouse 2 drawings. The foam panels 20 may be any thickness, butpreferably are in the range of about 3 inches to about 6 inches thickand most preferably are 4 inches thick. The foam panels 20 arepreferably 4 foot wide rectangular foam panels 20 that are cut to createa length equal to the height 22 of the walls 6.

[0040] Referring to FIGS. 5 and 6, foam panels 20 that are about 4 feetwide fit together side-by-side vertically. The vertical joint 24 betweenthe panels 20 is preferably joined with an adhesive product. However,other means for joining the panels 20 include tape, toothpicks, woodskewers, and other similar devices that may be used to temporarilysecure foam pieces. In the preferred embodiment, Enerfoam® (FlexibleProducts Company of Canada, Inc., Ontario, Canada) is used between thefoam panels 20. The foam panels 20 of each wall 6 are glued together andthen each wall 6 is glued to the other walls 6. For example, FIG. 5shows the panels 20 for the front 12 of the house 2 joined together.FIG. 6 shows the glued together panels 20 for the back 14 of the house2. FIGS. 7 and 8 show the joined panels 20 for the right 18 and left 15sides of the house 2. In addition, the panels 20 for the front 12 andback 14 are cut on the top edge 26 to match approximately the pitch ofthe roof 28. In addition, the panels 20 for the left 16 and right 18walls 6 are beveled 30 (cut on a slant) on the top edge 26 to about thesame angle as the pitch of the roof 28, as shown in FIGS. 7, 8, and 16.

[0041] In another embodiment of the present invention, the foam panels20 are juxtaposed one above the other to form walls 6 instead of beingjuxtaposed vertically side-by-side. The horizontal panels 20 areattached to each other through the means described above.

[0042] As shown in FIGS. 1 and 13, interior walls 5 of the house 2 arepreferably constructed of the same foam panels 20 as used for the outerwalls 6 of the house 2. The foam panels 20 are pre-cut to a length 22(FIG. 5) to match the distance from the foundation 4 (FIG. 1) to theroof 28 (FIG. 14) of the house 2 at the position where the interior andexterior walls 6 are placed. As shown in FIGS. 7, 8, and 13, the topedge 26 of each panel 20 is preferably beveled 30 to approximately matchthe pitch of the roof 28.

[0043] Referring to FIG. 14, the roof 28 is constructed of foam panels20 which may be cut in a wide variety of dimensions. In the preferredembodiment, the roof 28 is constructed of rectangular foam panels 20which are about 8 inches thick, about 4 feet wide, and long enough toallow for about a 2 foot overhang 32 on the left 16 and right 18 sidesof the house 2. The roof thickness preferably varies from about 6 toabout 12 inches. FIG. 14 shows a top view of the roof 28 where thepanels 20 of the roof 28 are superimposed over the walls 6 of the house2. The roof overhang 32 preferably exists on all sides of the house 2.FIG. 15 shows the same roof 28 layout prior to joining the roof panels20 together. Preferably, the roof panels 29 for each side 16, 18 of thehouse 2 are joined together along the vertical joints 24 between thepanels 20 with an adhesive material. Further, the top edge 27 of thepanels 20 are joined by an adhesive material at the apex 34 of the roof28.

[0044]FIG. 16 shows an alternative embodiment of the invention where theleft side 16 and right side 18 of the walls 6 are received on their topedge 26 into a notch 36 cut into the roof panels 20. FIG. 17 shows anembodiment of the invention where an interior wall 6 of the house 2 ispositioned under the apex 34 of the roof 28. The roof panels 20 containa notch 36 that receive the top edge 26 of the wall panels 20. Notch 36,as shown in FIG. 16, is made one inch deep into roof panels 26 toreceive the top edge 26 of wall panels 20, which have bevel 30. Alsoshown in FIG. 16 and FIG. 17, a 2-inch by 4-inch foam roof spline 42,preferably constructed of a EPS foam, is used to join roof panels 26along their side edges. Each roof panel 26 is notched to accommodatespline 42.

[0045] In another alternative embodiment of the invention, the roofpanels 20 are cut with an outer roof notch 37 from the front 12 to theback 14 of the house 2. The outer roof notch 37 is positioned over thewalls 6 on the left 16 and right 18 sides of the house 2. As shown inFIG. 16, the outer roof notch 37 is semi-circular and has a 3-inchdiameter. The outer roof notches 37 on the left 16 and right 18 sides ofthe house 2 are then filled with an outer roof rib 38 that is cut tomatch the shape of the outer roof notches 37. The outer roof rib 38 runsthe entire length of the notch 37. In another alternative embodiment ofthe invention, an apex roof notch 39 is cut along the top edge 27 of theroof panels 20. The dimensions of the notch 39 may vary greatly but arepreferably about 2 inches deep and about 2 inches wide to create acombined notch 39, after the roof panels 20 are joined at their top edge27, of about 2 inches deep and about 4 inches wide. An apex roof rib 40is cut to approximately match the shape of the apex roof notch 39. Theapex roof rib 40 is placed into the apex roof notch 39 and runs thelength of the apex 34 of the roof 28. As shown in FIG. 18, under theribs 38, 40, a hurricane strap 58 can be placed across the roof 28 andconnected to the foundation 4, in an alternative embodiment of theinvention. A hurricane strap 58 may be made of a wide variety ofmaterials, but is preferably a thin strap of about 18 or 22 gauge steel.

[0046] The ridge detail in FIG. 17 shows a roof angle of about 14° fromthe horizontal (or a 4 to 1 ratio vertical to horizontal). However, theroof angle may be varied from a flat roof to one with a steep pitch.

[0047] In another preferred embodiment of the invention, some or all ofthe wall panels 20 may be joined at their vertical joints 24 withsplines 42. Accordingly, where all panels 20 in the framework-freebuilding system of the present invention are joined at their verticaljoints 24 with splines 42, every panel of the plurality of panels isjuxtaposed and connected via a spline 42, such as a foam spline, to twopanels 20. Specific spline 42 connections are shown in FIGS. 9, 10, 11and 12. For example, foam panels 20 having grooves are juxtaposed andconnected via a foam spline 42 located in the grooves of juxtaposedpanels to create a plurality of walls and a roof. In one embodiment ofthe present invention, at least one panel 20 has grooves along each ofits two opposing edges 24 so that the said at least one panel 20 isjuxtaposed and connected via a foam spline to two other panels 20. Theshape of the splines 42 may vary greatly, but a spline preferably has arectangular cross-section and extends most of the length of a panel 20.FIG. 9 is a cross-sectional view of FIG. 1 at A, showing a spline 42with the cross-sectional dimensions of about 1.5 inches by about 3.5inches. FIG. 10 shows a cross-sectional view of FIG. 1 at B, where aspline 42 helps connect a wall panel 20 at a corner 48 of the house 2.The spline 42 connects the vertical side or edge 24 of one panel 20 witha side 46 of another panel 20, a corner panel. FIGS. 11 and 12 showalternative embodiments of the invention where three wall panels 20 arejoined together. Splines 42 may be used to join one or more of the threewall panels 20 together. Further, the outline of splines 42 joining roofpanels 20 is shown in FIGS. 16 and 17. Still further, where at least onepanel 20 has grooves along each of its two opposing edges 24 to allow itto be juxtaposed and connected via a spline 42 to two other panels 20,one or both of the two other panels 20 can selected from the groupconsisting of a corner panel which has a groove along its side 46 (FIG.10), an interior wall panel that has a groove along its side 46 (FIG.12), a panel which has a groove along its edge 24 (FIGS. 9 and 11) and apanel which has a groove along each of its two opposing edges 24.

[0048] After the walls 6 and roof 28 are constructed, openings fordoors, windows, electrical outlets and other features are cut into thefoam 20. As seen in a cross-section detail in FIG. 1 at A, the entirestructure 2 is coated inside and out with a cementitious material 50that forms a load-bearing shell 52 that sticks directly to the foampanels 20.

[0049] In other preferred embodiments, architectural details are addedto the house 2 such as texture, color, decorative tile or brick, orarchitectural features that provide the house 2 with contours. Foam trimpanels 20, for example may be placed at the corners 48 of the house 2and around doors and windows to provide architectural contours.Architectural features of great variety may be achieved.

[0050] The preferred method of this invention is a new method forconstructing a building system 2 without steel or other support systems.Erecting the building system 2 involves first preparing a house site.Traditional methods of site preparation are well-known to those skilledin the art and include leveling of the ground, as well as soil testing.Soil conditions vary significantly such that a geotechnical report ispreferably prepared prior to house 2 construction; this involves boringinto the soil to a depth of about 10 feet and taking soil samples.Geotechnical tests performed on the soil typically determine compactionand expansion rates for the soil, thus helping to determine housefoundation requirements.

[0051] Compacted fill is preferably placed on the site to provide apartial vapor barrier between the foundation 4 and the earth. A concretefoundation 4 is then prepared, which is preferably a traditionalconcrete slab 4. In the preferred embodiment, a trench 10 is dug aroundthe perimeter 8 of the foundation 4 and under the interior walls 6 ofthe house 2. Referring to FIGS. 3 and 4, cross-sections of the trenches10 from FIG. 2 are shown across the lines A-A and B-B respectively.Preferably, the trenches 10 are about 4 inches deep, but their depth maybe varied greatly. After the trenches 10 are dug, welded wire fabric orreinforced steel 9 is laid on the site. In the most preferredembodiment, welded wire fabric 9 is laid across the foundation 4 areaand bent into the perimeter trenches 10. The wire mesh 9 is preferablyNo. 6 size wire mesh 9 which has wires perpendicular to each other at 6inch intervals. Ready-mix concrete is preferably poured into thefoundation 4, vibrated into place, and floated smooth, as is well-knownto those skilled in the art.

[0052] In an alternative embodiment, a system of I-beams is laid on thefoundation 4 around the perimeter 8 of the house 2 as well as under theinterior walls 6. Additional beams may also be placed. Once the beamsare placed, concrete is poured over them to create a foundation 4.

[0053] In the preferred embodiment, the concrete slab 4 is poured to adepth of 2 inches, except where the trenches 10 exist. The trenches 10preferably have a total depth of about 6 inches. The slab 4 in thepreferred embodiment of a small house 2 is about 24 feet by 20 feet.

[0054] Once the foundation 4 has cured, the pre-cut and numbered foampanels 20 are assembled. In one alternative embodiment of the invention,a bottom track 7 is placed on the foundation 4 along the perimeter 8 ofthe house 2. The bottom track 7 is preferably the same width anddiameter as the foam 20 and can be flat or have edges on each side toprovide a C-shaped track. The track 7 is preferably glued to thefoundation 4. Alternatively, it may be attached with anchor bolts orramsetted nails. After the bottom tracks 7 are attached, the walls 6 areerected one by one. First, the panels 20 for each wall 6 are joinedtogether, preferably by glue. If a spline 42 is used in the joints 24between wall panels 20 (as described above), the splines 42 are insertedbetween the consecutive wall panels 20. Preferably, the splines 42 aremade of foam, for example, EPS foam. In one preferred embodiment, thesplines 42 and panels 20 are adhered together with a foam adhesiveaerosol spray such as Enerfoam®. Once a wall 6 is constructed, it is setonto the bottom track 7, if one is used, and erected using temporarybracing, which bracing is well-known to those skilled in the art. Oncethe outer walls 6 are erected, the interior walls 6 are erected. Afterall the walls 6 of the house 2 are assembled and temporarily braced, theroof 28 is assembled. The roof panels 20 are pre-cut and numbered forease of assembly. In the preferred embodiment, the roof panels 20 areglued together one-by-one on top of the house 2. Preferably, glue suchas Enerfoam® is used to help adhere the roof panels 20 to the walls 6where they meet at the sides 16, 18 of the house 2 and at the apex 34 ofthe roof 28. Modest temporary bracing, as is well-known to those skilledin the art, is placed under the roof panels 20.

[0055] Holes are cut in the walls 6 of the house 2 for doors, windows,electrical circuits, plumbing, and as otherwise needed. In oneembodiment, wood frames constructed preferably of 2×4's are installedaround the openings for the doors and windows. Openings for windows andother items are then covered with plastic, and then a cementitiousmaterial 50 that sticks directly to the foam 20 is sprayed onto thehouse 2. The cementitious material 50 is prepared in the preferredmethod by mixing together water, sand, lime, marble particles, Portlandcement, fibers, and an adhesive additive. In the most preferred method,about 2 gallons of water is mixed with about 100 pounds of sand. Then,about 2 gallons of water and about 100 pounds of sand are added andmixed. Then, about 60 pounds of marble particles and about 10 pounds oflime are mixed in, followed by about 1 gallon of water and about 94pounds of Portland cement. Then, about 0.5 pounds of quarter-inch fibersis mixed in, followed by about 1 gallon of water and about two gallonsof acrylic latex. Other additives may be mixed in to improve the cementproperties, such as a retarder. Further, up to about two more gallons ofwater may be mixed into the cement, depending on the heat, humidity andviscosity of the cement mix. The sand used in the process is preferablya blend of number three and four sands (about 50% of each) which may becommonly obtained (e.g., Specialty Sand, Houston, Tex.). The lime andmarble particles are available from suppliers such as General Terrazo inHouston, Tex. The marble is preferably in particles similar in size tonumber one size sand. Type one Portland cement is preferably used andcan be obtained from concrete companies or hardware stores such as HomeDepot. The fibers used are preferably quarter-inch fibrillatedpolypropylene fibers (Fibermesh, Synthetic Industries, Houston, Tex.).However, the fibers may be made of many materials including fiberglassor other plastics, or metal.

[0056] In another embodiment, the cement mixture 50 is comprised ofapproximately 200 pounds of Masonry sand which is a blend of numberthree and four sands (about 50% of each); approximately 94 pounds ofType one Portland cement; about 5 gallons of water; approximately 1.5gallons of MICROGEL™; and about ½ pound quarter-inch fibrillatedpolypropylene fibers.

[0057] This cement mixture 50 is preferably mixed in the mixer of themachine that sprays the cement 50 onto the house 2. In the preferredembodiment, the spraying machine is a mixer/pump such as the PutzmeisterP11S Vario Worm Pump (Germany). Other machines that may be used to mixand spray the cementitious coating 50 include the Spray Force® drywalland plastering machine, model Hurricane 350 (Spray Force Manufacturing,Inc., Fresno, Calif.) or the Allentown Powercreter® (Master Builders,Inc., Cleveland, Ohio or Allentown Co., Allentown, Pa.).

[0058] The spraying machine has a rubber hydraulic hose (available fromPutzmeister) attached to its output that is preferably about 75 feetlong. The first approximately 25 feet of the hose has about a 3 inchdiameter, the second approximately 25 feet of hose has about a 2 inchdiameter; and the last approximately 25 feet of hose has about a 1.5inch diameter. An adjustable nozzle, such as the type used for stucco orgunnite, is attached to the end of the hose. It preferably has a{fraction (3/16)} inch to a ¾ inch variable tip diameter. In addition,an air hose is attached from the spray machine to the nozzle to provideair entrainment into the cement mix 50 as it blows from the nozzle, asis well-known to those skilled in the art. By trial and error, the airpressure and the nozzle tip size are adjusted. Preferably, a nozzle tipsize of ⅜ inch is used with about 50 psi of air pressure when the airtemperature is 95°; about 45 psi of air at 80°; and about 40 psi at 75°.

[0059] Before the cement 50 is mixed in the spray machine, a primermixture is made and pumped into the hose. The primer is comprised ofabout 60 lbs. of lime and about 4 gallons of water, which is mixed forabout 3 minutes or until complete mixing occurs. Once the sprayablecement mixture 50 is ready to spray onto the house 2, the primer ispumped into buckets for reuse. Then, the cement mixture 50 is sprayedonto the house 2 in a thin coating 54, as shown in FIG 1A. A singlecoating 54 in the range of about ¼ inch to about ¾ inch is preferablyapplied. In the most preferred embodiment, two thin coatings 54 areapplied. The first coating 54 is applied to a thickness of about ¼ inchand allowed to cure for about 30 minutes or until a permanent setoccurs. Then, a second coating 54 is sprayed on to a thickness of about¼ inch. The house 2 then cures and attains its final compressivestrength as a load-bearing shell 52 around the underlying housematerials. In an alternative embodiment, the cement coating 54 isapplied by troweling or other non-spray methods. Temporary bracing ofthe walls 6 and roof 28 is removed once the coating 52 has cured forabout three days.

[0060] Before the coating 54 dries, it may be decorated by etchingpatterns into it; by pressing rocks or other appliques into it; bytroweling the surface smooth, and by many other decorative techniques.Alternatively, after the cement 54 dries, appliques may be screwed intothe cement 54. After the house 2 has cured for about five days, it maybe painted or further water sealed. An elastomeric paint such asHydrostop® accomplishes both water sealing and provides color to thehouse 2. The paint or sealant is preferably applied by rolling, airlesspaint gun, or paint brush. In another preferred embodiment of themethod, powdered dyes are added to the cementitious material 50 when itis being mixed so that the sprayed cementitious material 50 is in apreferred color, thus obviating any need for painting thereafter.

[0061] Before the cementitious material 50 is applied, architecturaldetails can easily be added to the structure around windows, doors,eaves, corners and in other areas by applying additional foam pieces 20to the walls 6. Such architectural foam pieces 20 may be tooth-picked orglued into place as described above.

[0062] In another preferred embodiment of the invention, anapproximately 1 inch by 4 inch wooden strip is attached along the sideof the concrete foundation 4. This provides a ledge 56, preferably madeof wood, above which the cementitious material 50 is sprayed. The stripis elevated above the ground surface so that shifting ground does nottouch the cementitious coating 52. In another alternative embodiment,the foam panels 20 are inset about one inch from the edge of theconcrete foundation 4 creating a ledge above which the cementitiousmaterial 50 may be sprayed. The cementitious material 50 is then sprayedon the wall panels 20, but not over the concrete foundation 4.

[0063] Although the description of the preferred invention is directedto a small house, the building system may be used in many applications.For example, the building system may be used for sheds, barns, boathouses, large houses and commercial buildings.

[0064] Common engineering elements such as pumps, gages, valves,controllers, material selection and the like are not shown or describedexcept when necessary for the understanding of the invention, since forthe most part, selection and placement of such equipment is well withinthe skill of the ordinary engineer. Although the above method andapparatus are described in terms of the above preferred embodiments,those skilled in the art will recognize that changes in the process andapparatus may be made without departing from the spirit of theinvention. Such changes are intended to fall within the scope of thefollowing claims.

We claim:
 1. A framework-free building system comprised of: a concretefoundation; a plurality of foam panels, said foam panels juxtaposed tocreate a plurality of walls and a roof; and a cementitious coatingapplied to said walls and roof to form a load-bearing shell.
 2. Theframework-free building system of claim 1 wherein said cementitiouscoating is sprayed on.
 3. The framework-free building system of claim 1wherein the foam panels are comprised of expanded polystyrene.
 4. Theframework-free building system of claim 1 wherein the foam panels arecomprised of modified expanded polystyrene with a pound density in therange of about 1.0 to about 2.0.
 5. The framework-free building systemof claim 1 wherein the foam panels are comprised of polyurethane.
 6. Theframework-free building system of claim 1 wherein the foam panels have athickness in the range of about 3 inches to about 6 inches.
 7. Theframework-free building system of claim 1 further comprising a temporaryconnector between the foam panels.
 8. The framework-free building systemof claim 7 wherein the temporary connector is selected from a groupconsisting of an adhesive, tape, toothpicks, screws, and wood skewers.9. The framework-free building system of claim 1 wherein the roof pitchhas a range from flat to steep.
 10. The framework-free building systemof claim 1 wherein the foam panels of a front wall and a back wall havea slanted top edge to match approximately the pitch of the roof, and thefoam panels of a side wall are beveled on the top edge to about the sameangle as the pitch of the roof.
 11. The framework-free building systemof claim 1 wherein the foam panels of the roof have a thickness in therange of about 6 inches to about 12 inches.
 12. The framework-freebuilding system of claim 1 wherein the roof extends out over theexterior walls to create an overhang.
 13. The framework-free buildingsystem of claim 1 further comprising a notch in an underside of the roofto correspond to the walls, wherein the notch receives the top edge ofthe walls.
 14. The framework-free building system of claim 1 wherein atop side of the roof has outer roof notches to receive hurricane strapsthat connect to the foundation.
 15. The framework-free building systemof claim 14 wherein outer roof ribs are placed in the outer roofnotches.
 16. The framework-free building system of claim 1 wherein thefoam panels are connected side by side thereby creating vertical joints.17. The framework-free building system of claim 16 wherein the foampanels are joined at their vertical joints with foam splines.
 18. Theframework-free building system of claim 17 wherein said splines extendmost of the length of the foam panels.
 19. The framework-free buildingsystem of claim 1 wherein the foundation has a bottom track attached toa perimeter of said foundation to receive a bottom edge of the walls.20. The framework-free building system of claim 1 wherein thecementitious material is comprised of water, sand, lime, marbleparticles, Portland cement, fibers, and an adhesive additive.
 21. Theframework-free building system of claim 1 further comprising a woodledge attached to one or more sides of the foundation wherein the woodledge forms a barrier above which the cementitious material is sprayed.22. A method of constructing a framework-free building comprising thesteps of: constructing a concrete foundation; juxtaposing foam panels toform walls and a roof; and applying a cementitious coating onto thewalls and roof to form a load-bearing shell around the house.
 23. Themethod of constructing a framework-free building of claim 22 furthercomprising the steps of pre-cutting and numbering consecutively the foampanels for assembly at the construction site.
 24. The method ofconstructing the framework-free building of claim 22 further comprisingthe steps of placing a bottom track on the foundation along theperimeter of the house and placing the walls into the bottom track. 25.The method of constructing a framework-free building of claim 22 whereinthe step of applying the cementitious material is by spraying.
 26. Themethod of constructing a framework-free building of claim 22 furthercomprising the step of etching decorative patterns into the cementitiouscoating before it dries.
 27. The method of constructing theframework-free building of claim 22 further comprising the step ofadding powdered dyes to the cementitious coating while it is beingmixed.
 28. The method of constructing the framework-free building ofclaim 22 further comprising the step of temporarily connecting thejuxtaposed foam panels.
 29. A framework-free building system comprising:a foundation; a plurality of foam panels, said foam panels juxtaposed tocreate a plurality of exterior walls and interior walls and a roof; anda foam connector between the foam panels, said foam connector beingselected from the group consisting of a foam adhesive, a foam spline, afoam spline combined with an adhesive, and a spline combined with a foamadhesive. wherein said interior walls comprise foam panels pre-cut to alength to match the distance, from the foundation to the roof at aposition where the interior walls are placed.
 30. The framework-freebuilding system of claim 29, wherein the foam panels comprise expandedpolystyrene.
 31. The framework-free building system of claim 29, whereinthe foam panels comprise polystyrene or polyurethane.
 32. Theframework-free building system of claim 29, wherein the foam adhesive isa polyurethane foam adhesive.
 33. The framework-free building system ofclaim 29, wherein the foam panels of a front or a back wall have aslanted top edge to match approximately the pitch of the roof.
 34. Theframework-free building system of claim 29, wherein the foam panels of aside wall are beveled on the top edge to about the same angle as thepitch of the roof.
 35. The framework-free building system of claim 29,wherein the roof extends out over the exterior walls to create anoverhang.
 36. The framework-free building system of claim 29, furthercomprising a notch in an underside of the roof panels to correspond tothe walls, wherein the notch receives two sides of the walls on theirtop edge and the roof panels are glued to the wall panels.
 37. Theframework-free building system of claim 29, wherein a top side of theroof has outer roof notches to receive hurricane straps that connect tothe foundation.
 38. The framework-free building system of claim 37,wherein outer roof ribs are placed in the outer roof notches.
 39. Theframework-free building system of claim 29, wherein the foam panels areconnected side-by-side, thereby creating vertical joints glued together.40. The framework-free building system of claim 39, wherein the foampanels are joined at their vertical joints with foam splines and gluedtogether.
 41. The framework-free building system of claim 29, whereinthe foundation has a bottom track attached to the perimeter of saidfoundation to receive a bottom edge of the wall panels, wherein the wallpanels are polystyrene.
 42. The framework-free building system of claim29, wherein an interior wall is positioned under the roof at an apex ofthe roof and the roof panels forming said apex contain a notch thatreceives the top edge of said interior wall.
 43. The framework-freebuilding system of claim 29, wherein roof panels further comprise anapex roof notch along their top edge, and an apex roof rib is placedinto the roof notch and runs along the length of the apex of the roof.44. A framework-free building system, comprising: a foundation having abottom track on the foundation to receive the bottom edge of a foampanel wall; and a plurality of foam panels, said foam panels juxtaposedto create a plurality of walls at least comprising exterior walls and aroof, the roof comprising a notch in an underside of the roof panels tocorrespond to the walls, wherein the notch receives the top edge of thewalls and the roof panels are glued to the wall panels.
 45. Theframework-free building system of claim 44, wherein said foam panels aremade of polystyrene.
 46. The framework-free building system of claim 44,further comprising interior walls which comprise foam panels pre-cut toa length to match the distance from the foundation to the roof of thestructure at a position where the interior walls are placed.
 47. Aframework-free building system, comprising: a foundation; and aplurality of foam panels, said foam panels juxtaposed and connected viaa foam connector to create a plurality of walls and a roof, wherein thefoundation has a bottom track attached on said foundation to receive abottom edge of the wall panels, wherein the bottom track is a C-shaped,flat track having vertical edges on each side.
 48. The framework-freebuilding system of claim 47, wherein the foam connector is selected fromthe group consisting of a foam adhesive, a foam spline and a foam splinecombined with an adhesive.
 49. A method of constructing a framework-freebuilding, comprising: constructing a foundation; juxtaposing foam panelsto form a structure having walls and a roof; and placing a bottom trackon the foundation along the perimeter of the foundation and gluing thewalls into the bottom track.